val=list(map(float,input().split()))
if(val[0]>val[2]):
    x=(val[0]-val[2])**2
else:
    x=(val[2]-val[0])**2
if(val[1]>val[3]):
    y=(val[1]-val[3])**2
else:
    y=(val[3]-val[1])**2
    
length=(x+y)**0.5
print(length) val=list(map(float,input().split())) val list(map(float,input().split())) list map(float,input().split()) map float input().split() ().split () input split if(val[0]>val[2]):
    x=(val[0]-val[2])**2
else:
    x=(val[2]-val[0])**2 val[0]>val[2] val[0] val 0 val[2] val 2 x=(val[0]-val[2])**2 x (val[0]-val[2])**2 val[0]-val[2] val[0] val 0 val[2] val 2 2 x=(val[2]-val[0])**2 x (val[2]-val[0])**2 val[2]-val[0] val[2] val 2 val[0] val 0 2 if(val[1]>val[3]):
    y=(val[1]-val[3])**2
else:
    y=(val[3]-val[1])**2
     val[1]>val[3] val[1] val 1 val[3] val 3 y=(val[1]-val[3])**2 y (val[1]-val[3])**2 val[1]-val[3] val[1] val 1 val[3] val 3 2 y=(val[3]-val[1])**2 y (val[3]-val[1])**2 val[3]-val[1] val[3] val 3 val[1] val 1 2 length=(x+y)**0.5 length (x+y)**0.5 x+y x y 0.5 print(length) print length x=(val[2]-val[0])**2 (val[2]-val[0])**2 x y=(val[1]-val[3])**2 (val[1]-val[3])**2 y val=list(map(float,input().split())) list(map(float,input().split())) val x=(val[0]-val[2])**2 (val[0]-val[2])**2 x length=(x+y)**0.5 (x+y)**0.5 length y=(val[3]-val[1])**2 (val[3]-val[1])**2 y
val=list(map(float,input().split()))
if(val[0]>val[2]):
    x=(val[0]-val[2])**2
else:
    x=(val[2]-val[0])**2
if(val[1]>val[3]):
    y=(val[1]-val[3])**2
else:
    y=(val[3]-val[1])**2
    
length=(x+y)**0.5
print(length)
